I have a question that recently had practical implications.
We were sitting in a restaurant and some older people walked
in as they had a booking. The restaurant management confused the
booking and it turns out that there was no space for them to be
seated. They were angry that we as the younger generation did
not show "derech eretz" by getting up for them and offering
our table. We were surprised at this and my question is, is there
an obligation to get up for older people in a commercial setting
where we are paying customers like all other customers? What
is the halacha and would there be a difference between a bus situation
and a restaurant?

Dear David Walles,

First of all, let's not confuse "old" with "sick."
The Torah teaches us to honor the elderly even if they are healthy,
and to help sick people even if they are young. So, in order
not to confuse these issues, let's assume we are talking about
healthy 70 year olds who need no physical assistance. Assuming
this, you were not obligated to give up your table. Depending
on the situation, however, it may have been a good thing to do.

The Torah says, "Rise before an old person, and honor the
presence of a sage." The Shulchan Aruch defines "old"
as age 70. If a 70 year old person walks by, you must stand.
This is not in order to offer him your seat, but rather as a
way of showing honor by recognizing his presence.

The obligation to show honor is not limited to standing up, but
can also involve giving your seat, helping with a package, or
otherwise offering assistance. However, one is not required to
incur a financial loss as a result. Since there is a definite
monetary value in having a seat in a restaurant, you were therefore
not required to offer your seat. Although the same argument can
be made for a bus seat, as you have paid for the right to sit
there (again, assuming the older people are physically able to
stand in relative comfort) nevertheless one should stand for an
elderly person on a bus or subway.

That having been said, keep in mind that "derech eretz
kadma l'Torah" - good manners and character traits are
a prerequisite to observing the Torah. Depending on the situation,
simple etiquette and common sense may require you to stand. This
is especially true if you wear a yarmulke, because people
tend to generalize about others based on their dress - therefore,
when you wear a yarmulke you are "Judaism's ambassador"
and must therefore keep to a higher standard than the letter of
the law requires.

In the case of a restaurant booking, I don't think this applies,
as it is normal to be seated on a reservation or "first come
first served" basis, and one is not expected to relinquish
his seat for another. In a pizza shop, or other informal setting
where people "eat and run," you should give up your
seat.